Air-break switch



H. E. SEAMAN El AL July 4, 1950 AIR-BREAK SWITCH 2 Sheets-Sheet 1 FiledNov. 19, 1947 INVENTORS. Zesir CHOJ' HQWMESeQmcm.

H. E. SEAMAN El AL July 4, 1950 AIR-BREAK SWITCH F iled Nov. 19, 1947 2Sheets-Sheet 2 Patented July 4, 1950 AIR-BREAK SWITCH Harold E. Seaman,Cleveland Heights, and Lester 0. Hart, Shaker Heights, Ohio, assignorsto Iii-Voltage Equipment Company, Cleveland, Ohio, a corporation of OhioApplication November 19, 1947, Serial No. '$86,890

6 Claims. 1

The present invention relates to an electric switch and moreparticularly to an electric switch of the type used to isolate highvoltage circuits in high voltage substations and the like.

Specifically the present invention is an improvement on United StatesLetters Patent,

1,829,349 and 1,962,305, both assigned to the same assignee as thepresent application.

-In switches of the type disclosed and claimed in the above mentionedLetters Patent of the United States there is provided a mechanism whichcauses the switch arm or blade to move endwise along the longitudinalaxis thereof at the moment of engagement and disengagement with thestationary contact, thus insuring positive movement under all conditionsparticularly when covered with snow and ice in the winter time. Duringthe remainder of the cycle of opening or closing operation the switchblade swings about a pivot in a conventional manner.

It is an object of the present invention to provide a simple mechanismfor a high voltage switch which moves the switch blade longitudinallywhen it is near the closed circuit position,

which swings the blade in an are about a pivot u point during otherportions of its travel, and which gives smooth and positive control ofthe switch blade at all times.

It is another object of the present invention to provide a simplemechanism for producing the above movement which comprises only a.series of pivoted links related in a simple manner.

It is a further object of the present invention to provide a mechanismwhich may be operated under all conditions of service and in which anyrequirement for replacement or repair in the operating elements isreduced to a minimum.

Still another object of the present invention is the provision of animproved operating mechanism for a, switch in which two distinctmovements of the switch blade occur during both the opening and theclosing operation of the switch in response to rotary movement of asingle insulator connected by a single link with the remainder of theswitch blade operating mechanism.

Further objects and advantages of the present invention will becomeapparent as the following description proceeds and the features ofnovelty which characterize the invention will be pointed out withparticularity in the claims annexed to and forming a part of thisspecification.

For a better understanding of the present invention reference may be hadto the accompanying drawings in which:

Fig. l is an elevational view of the switch of the present inventionshown in the closed circuit position;

Fig. 2 is an enlarged plan view of a portion of the switch of Fig. 1showing the operating mechanism thereof-in the position assumed when theswitch is closed;

Fig. 3 is an enlarged elevational view of the operating mechanism ofFig. 1 showing the switch in the closed .circuit position; and

Fig. 4 is a View similar to Fig. 3 showing in solid lines the positionof the operating mechanism for an intermediate position of the switchand in dotted lines the position of the operating mechanism for the openposition of the switch.

It will be understood that the present invention is adapted for use witheither single pole or multi-pole operation. To simplify the drawingsonly a single pole of the switch is illus. trated. In a multi-poleswitch additional units identical with the unit shown in Fig. l of thedrawings are provided with links interconnecting the operatingmechanisms to insure simultaneous operation of the switch blades. 7

Referring now to the drawings there isillustrated a switch generallyindicated at It embodying the present invention. This switch comprises abase member H formed of channel iron or any other suitable material,which will provide a rigid member for supporting the switch contacts andoperating means. As illustrated the base H is disposed in a horizontalposition. It should be understood, however, that this base might equallywell be disposed in a vertical position and the illustrated position isby way, of example only. Secured to the base H are a pair of fixed orstationary insulators l2 and 13 mounted in spaced relationship on thebase It, and a movable insulator l4 positioned between the insulators l2and It. The insulators i2 and I 3 are provided with suitable means forscouring them to the base H. The insulator M on the other hand includesa downwardly extending shaft l5 which is adapted for rotation in asuit:- able. bearing I6 mounted on the base H. The end of the shaft 15depending below the base I I is provided with a hexagonal end l5a whichmay be engaged by a suitable manual operating lever or the like to causerotation of the insulator I4. Preferably the bearing and shaft dependingbelow the base ii are provided with a suitable sleet hood ll.

For the purpose of operating the switch in as a multi-pole switch one ormore crank arms l8 may be provided to rotate with the insulator shaftl5. As illustrated the crank arm 18 is provided with an operating eye l9which may be connected to suitable rods for interrelating the operationof the plurality of poles of the multi-pole switch to insuresimultaneous operation thereof. It will be understood that where asingle pole switch is employed the crank arm |8 may be dispensed with.Also instead of applying a crank to the hexagonal extension |a power foroperating the switch may be applied through a suitable link connected tothe crank arm 18 as will be understood by those skilled in the art.

In order to support electrical conductors which together with the switchcomprise the circuit to be controlled, the insulator l2 has mountedthereon a hinge base and terminal support 2| while the insulator I3 hasmounted thereon a contact support 22. It will be understood thatthesupports 2| and 22 are suitably fastened to their associated insulatorsl2 and i3 in any conventional manner. Mounted on the support '22 is thestationary contactmeans or assembly generally designated at 23. Thestationary contact itself is not visible in the drawings since it iscovered by a sleet hood 24 preferably formed of bronze or the like. Itwill be understood however that the stationary contact may comprise anysuitable contact capable of carrying the currents at the high voltagesinvolved and in general may comprise spring biased contact jaws forengaging and receiving therebetween the bladelike contact portion of aswitch blade 23. The support 22 includes an extension to which asuitable terminal 21 may be bolted or otherwise secured which terminal21 is electrically connected to a suitable conductor 28. Also mounted onthe support 22 is a stationary arcing horn which cooperates with abifurcated multiple arcing horn 3| forming an extension of the switchblade 26. Although the high voltage switch of the present invention isan isolating switch rather than a circuit breaker so that it is notrequired to interrupt high currents, it may occasionally be necessary tointerrupt transformer magnetizing currents which is accomplished at thearcing horns 30 and 3| rather than at the current carrying contacts 23and 25. The support 22 further includes a contact base guide '33 forsupporting and guiding the movable contact 25 I fastened to the end ofthe switch blade 26 in its initial movement during the circuit openingoperation and in its final movement during the circuit closingoperation, when the switch blade moves endwise along its longitudinalaxis thereby guiding the blade during this movement. 7

The arrangement described thus far is similar to that disclosed in theprior patents referred to above and forms no part of the presentirrvention. The present invention is particularly concerned with theoperating mechanism to be described hereinafter associated with thehinge base and terminal support 2!. Preferably the support 2| is in theform of a casting having a terminal-like extension 2m to which issuitably bolted or otherwise fastened a terminal 35, to which isconnected the conductor 35. It will be apparent that the switch Itprovides the control path between the conductors 28 and 36. The castingor hinge support 2| includes a bifurcated portion 2|b which extendsforwardly over the rotatable insulator l4 and terminates in a bearing2|c for receiving the shaft 31 extending upwardly from the rotaryinsulator l4. The shaft '31 is suitably associated, as will be describedhereinafter with a top member 38 fastened to the rotatable insulator l4.The casting or support 2| further includes a raised portion 39, disposedsubstantially above the insulator 12, for receiving an adjustable capscrew 40, the purpose of which will become apparent as the followingdescription proceeds. A suitable lock nut 4| is provided to lock the capscrew 40 in any desired adjusted position.

In order to provide a simple operating mechanism causing endwisemovement of the switch blade 26 for a relatively small portion of theoperating stroke as Well as movement thereof for the major portion ofthe stroke there are provided links 42, 43 and 44. The link 43 is aUshaped member pivoted to the support 2| by means of a pin 45 whichextends through suitable openings defined in the ends of the arms of theU-shaped member 43 which are aligned with a suitable opening through thesupport 2|. With this arrangement one end of the link 43 is efiectivelypivoted about one point on support 2|. The link 42 is similarly pivotedwith reference to a fixed point related to the support 2|. Asillustrated the link 42 comprises a pair of link members 42a and 42b,best shown in Fig. 2 of the drawings, having one end thereof related bya pivot pin 46 with a sort of an eye bolt 41 threadedly mounted in thesupport 2|. With this arrangement the vertical position of the pivot pin46 is adjustable. A suitable lock screw 48 is provided to lock the bolt41 in any desired adjusted position. With this arrangement correspondingends of each of the links 42 and 43 are effectively pivoted about twospaced points on the support 2 i. As illustrated in the drawings thespaced points on the support 2| are so disposed that substantial spaceexists not only between a pair of vertical lines one through each of thespaced points 45 and 46 but also between a pair of horizontal lines, onethrough each of the points 45 and 46.

The link 44- is effectively a link interconnect ing the other ends ofthe links '42 and 43 not pivoted to the support 2|. Actually however,the so-called link 44 is much more than a link, as will become apparentfrom the following de scription, and it is preferably referred tohereinafter as movable member 44. As best illustrated in Fig. 2 of thedrawings the member 44 comprises a U-shaped portion 440, integrallyformed with an extension 4% connected to the bight of the U-shapedportion. The arms of the U-shaped portion 4 10. of the member 44 areconnected by means or a pin 49 with the U-shaped link 43, which latteris provided with extensions from the bight of the U-shaped portionhaving openings defined therein aligned with openings formed in the endsof the arms of the U-shaped portion 440., to accommodate the pivot pin59. The movable member 45 is also provided with 'a portion 44c extendingin the opposite direction from the portion 44b and in effect comprisingsomewhat of an extension of one of the arms of the U-shaped portion Me.This extension 440 is disposed between the link portions t-2a and 42b ofthe link 42 and is pivotally connected thereto by means of a pivot pin53 extending through aligned openings in the portions 42a, 42b and 440.This portion 430 of the link 44 also includes an upwardly extendingshoulder 5| which is adapted to act as a stop member for engaging thecap screw 4|] in the extreme open position of the switch to limit themaximum opening movement of the switch. Consequently the cap screw 4|)and the shoulder 5| cooperate to provide a switch opening stop device.The forwardly extending portion 44b of the movable member 44 includes asleeve or other suitable member 44d, preferably integrally formed withthe portion 44bto receive the relatively fixed end of the switch blade25. The blade 26 is illustrated as a rod of conducting material having acircular cross section. It will be understood that some other crosssection might equally well be employed. The sleeve 44d'includes a pairof ears 52 for accommodating a clamping bolt 53 whereby the blade 25 maybe rigidly clamped to the sleeve 44d and consequently the movable member44. It will be apparent therefore that the blade 26 effectively forms arigid part of the movable member 44 which in turn is fioatinglysupported at two spaced points to the ends of the links 42 and 43. Itwill also be noted from the drawings that the link 43 is a heavyweightcarrying link preferably comprising a heavy casting and is themain supporting link for the movable member 44, whereas the links 42 arelight control links for guiding the movement of this member and hencecarry little weight which is primarily sustained by the main supportinglink 42.

For the purpose of insuring a satisfactory electrical connection fromthe terminal 2Ia to the switch blade 26 without requiring the current toflow through relatively movable contacting surfaces there is provided aflexible conducting lead or braid 53 having one end clamped as by meansof the screw 54 to the support 2|. The other end is connected by meansof a bolt 55 with the bight section of the U-shaped portion 44a of thelink 44 as is best shown in Figs. 2 and 3 of the drawings. With thisarrangement the conductor 53 is in parallel with the links 42 and 43 toinsure a good current conducting path between the movable member 44 andthe support 2|.

In order to transmit any force causing rotation of the insulator M tothe operating mechanism of the present invention the member 38 supportedon the insulator l4 includes a crank arm 56 which may be an integralcasting with the member 38. Preferably the crank arm 56 has a pluralityof spaced ears such as 5611 including aligned openings therein which arealso aligned with the bearing 2lc for receiving the pin or shaft 31.Effectively therefore the bearing 2lc cooperates with the bearing I5rotatably to support the insulator H4 at either end thereof. The end ofthe crank arm 56 is connected to the link 44- by means of a universallink 58 having a universal connection at either end thereof. As bestshown in Fig. 2 of the drawings the movable member 44 has integrallyformed therewith a second U-shaped portion 59 which has the open endthereof opposite from the open end of the U-shaped portion 44a. Thissecond U-shaped portion is preferably disposed laterally from theoperating mechanism in the same direction that the crank arm 56 extendsfrom the insulator I4. A member 6|, indicated as a hexagonal member, isdisposed between the arms of the U-shaped portion 59 and pivotallyrelated thereto by means of an annular pin 5!] extending through thearms of the U-shaped portion 59 and the member 6|. Similarly the crank55 is provided with ears 5% between which is pivoted by means of anannular pin 62 the hexagonal member 53. The universal link 58 isprovided with U-shaped ends 5811 and 581) respectively which ends aredisplaced from each other by 90 as is apparent from the drawings. TheU-sh-aped end 58a is adapted to receive the pivotally supported member63 between the arms thereof and is pivotally related thereto by means ofthe pivot pin 55. Similarly the U-shaped end 58b is adapted to receivepivotally mounted hexagonal member Bl between the arms thereof and ispivotally related thereto, by means of the pin 66. It is apparenttherefore that universal movement of the link 58 with reference toeither the movable member 44 or the crank arm 56 is provided.

The operation of the present invention may best be understood byreference to the drawings where Figs. 1, 2 and 3 show the position ofthe operating mechanism for the closed portion of the switch. When aforce causing rotation of the insulator I4 in a clockwise direction .asviewed in Fig. 2 of the drawings is applied thereto, the crank arm 56causes this force to be transmitted to the universal link 58 tending tomove it to the left as viewed in Figs. 2 and 3 of the drawings. causesmovement of the movable member 44. Due to the particular relationship ofthe movable member 44 and the links 42 and 43 the initial movement ofthe link 58 mentioned above causes endwise movement only of the blade26. During this initial movement the relative vertical positions of thepivot points' lQ and 50- of the movable member 44- remain substantiallyunchanged thus insuring only longitudinal movement thereof. In Fig. 4 ofthe drawings there is illustrated in solid lines the position of theoperating mechanism at substantially the end of such initial endwisemovement of the blade during the opening operation of the switch. It isnoted that the movable member 44 is in substantially the same positionas in Fig. 3 except that it has been moved to the left. Upon continuedrotation of the insulator 3B the pivot point 50 moves rapidly downwardlyrelative to the pivot point 49, thereby causing the switch blade 25which is effectively integral with the movable member 44 to pivot aboutthe pivot point 49 so as to provide a large isolating gap between thestationary contact means 23 and the contact portion 25 of the blade 26.The position of the operating mechanism at the fully open switchposition is indicated in dotted lines in Fig. 4 of the drawings. In thisposition the shoulder 5| is in engagement with the stop comprising thecap screw 40. It will be observed from the successive positions of themechanism illustrated in the drawings that during the entire swingingmovement of the switch blade 25 that a line through the pivot points 46and 50 of the control links 42 closely approximates a right angle withrespect to the longitudinal axis of the switch blade 26.

During the circuit closing operation it is apparent that the sequence ofmovements described above will be reversed. The switch blade 25 firsteffectively pivots about pivot 49 until the solid line position of Fig.4 is reached whereupon continued closing movement of the switchcomprises endwise movement of the blade 25 along the longitudinal axisthereof.

The type of movement provided by the operating mechanism is advantageousfor several reasons. Since the swinging or pivotal movement of theswitch blade during the switch stroke is completed before the switchblade engages the contact member, the contact member and consequentlyits supporting insulator I4 is not exposed to the heavy impactordinarily borne by Such movement of the link 58 such members in manytypes of switches. Furthermore the engagement and disengagement of theswitch blade with the stationary contact means by an endwise movement ofthe switcharm rather than by a Swinging or pivotal movement isadvantageous since the leverage of the operating mechanism may beapplied to much better advantage thus insuring satisfactory operationduring conditions when the switch and operating mechanism are coveredwith snow and ice. Also since the upper side of the housing fl'fo'r the"stationary contact may be closed, and a lateral slot for the contactprovided, the construction is much more satisfactory from the standpointof protection against the entrance of sleet, rain or snow.

With the present invention a very simple con struction is providedincluding only a plurality of links so that the necessity of havingahousing for enclosing the mechanism is completely eliminated. Also avery inexpensive construction is provided which is simple to manufactureand which is sturdy and foolproof in operation.

It will be apparent to those skilled in the art that the presentinvention is not limited to the particular construction and arrangementshown and described but that changes and modifications may be madewithout departing from the spirit and scope of the present invention. Itis aimed in the appended claims to cover all such changes andmodifications that fall within the true spirit and scope of the presentinvention.

What is claimed as new and desired to be secured by Letters Patent ofthe United States is:

1. In an electric switch, a pair of spaced supports mounted oninsulating means, stationary contact means mounted on one of saidsupports, a pair of links each having one end pivotally supported to adifferent one of two spaced points on the other of said supports, saidpoints being so disposed that a substantially greater separation existsbetween a pair of horizontal lines one through each of said points thanthe separation between a pair of vertical lines one through each of saidpoints, a movable conducting member having a plurality of pivot pointsthereon, one of said links being shorter than the other, means pivotallyrelating one of said pivot points and the other end of one of saidlinks, means piv-otall-y relating another of said pivot points and theother end of the other of said links, a switch blade rigidly fastenedand electrically connected to said member and arranged to movetoward'and away from said stationary contact means during closing andopening of said switch, and means for applying an operating force tosaid member to cause movement thereof, said links and member being sorelated that operation of said last mentioned means causes swingingmovement of said switch blade for the major portion of its movementtogether with an 'endwise movement of said switch blade along itslongitudinal axis when said switch blade is near its closed circuitposition.

2. An electric switch comprising a pair of spaced supports mounted oninsulating means, stationary contact means mounted on one of'saidsupports, a pairof links comprising a main supporting link and a controllink each having one end pivotally supported to a different one of twospaced points on the other of said supports, said control link beingshorter than said main link, a-mov'able conducting member havingaplurality of pivot points thereon, means pivotallyrelatin'g one of saidpivotpoints and theother end of one of said links, means pivotallyrelating an": other of said pivot points and 'the other :end of theother of said links, a switch blade of circular cross-section rigidlyfastened and electrically connected tosaid member and arranged'to'movetoward and away from said stationary con'tact means during closing'andopening of said switch;- and means including "a rotatable insulator forapplying an operating force to said member to cause movement thereof,said links and member being so related that operation of said lastmentioned means causes swinging movement of said switch blade for themajor portion of its movemeiit together 'with' an endwise movement ofsaid switch blade along its longitudinal axis when'said switch blade isnear its closed circuit position, a line through the pivot points ofsaid control link closely approximating a right angle with thelongitudinal axis of said blade throughout the swinging-movementof saidblade.

3. In an electric'switch, a pair of spaced insulators,-a pair of:supports one mounted on each of said insulators, a first link, means'pivotally relating one end of said'first link and one of said supports,a second link, means pivotally relating one end of said second link tosaid one of said supports ate-point spaced both in'a vertical and a horizontal-direc'tion iromthe pivot point ofsaid first-link, the spacing insaid vertical direction substantially exceeding the spacing in saidhorizontal direction, a'mo vable member havingiaplurality of pivotpoints thereon, one of said links being longer than the other, meanspivotally 're-- la'ting one of said pivotpoints andthe-other end of saidfirst link, means pivotally relating another of said'pivot points andthe othereiid of said second-link, a-switch blade "rigidly fastened andelectrically connected to said member and arranged to move toward :andaway from said stationary contact duringclo'sing-and opening of saidswitch in response to movement of said member, a rotatable-insulatordisposedbetween said spaced insulators, a crank arm rotatablewithsaidrotatableinsulator, and means comprising a universal linkinterconnecting said crank arm andsaid member for transmitting anoperating force causih'g rotation of said'in'sulator to said member,said links and member "being so :related that operation of'said'lastmentioned means causes swinging mov'ementof said switch blade for themajor 1 portion of its movement together with 'an-eridwise movement ofsaid switch blade along its longitudinal axis when said switch bladeis'n'ear its closed circuit position.

4. In an electric switch, a pair-ofs'pacedsupports mou'nted oninsulating means, stationary contact mea'ns mounted on one'of-saidsupports, a-pairof-links each having'oneend pivotally supported to'adifierent one of two spaced points on the other of said supports, saidpoints being so disposed that a substantially greater separation existsbetween a pair of horizontal lines .one through each o'f-s'aid pointsthan-the separation between-apair of vertical lines one through-each ofsaid points, a movable conducting member having aplur'ality ofpivot'points thereon, means pivo'tall'yrelating one' of 's'aidz'pivotpoints and'the othe'r end of ons of said links,-means pivotallyrelating-another of said pivot points and the other end of the other ofsaid links, a switch blade rigidly fastened andelectrically connected tosaid memberand' arranged to move towardand away from s'aid stationarycontact during closing and'opening of said switch, a flexible conductorinterconnecting said member and the other :01

9 said supports, and means for applying an operating force to saidmember to cause movement thereof, said links and member being so relatedthat operation of said last mentioned means causes swinging movement ofsaid switch blade for the major portion of its movement together with anendwise movement of said switch blade along its longitudinal axis whensaid switch blade is near its closed circuit position.

5. In an electric switch, a pair of spaced insulators, a pair ofsupports one mounted on each of said insulators, a stationary contactsupported on one of said insulators, a control link, adjustable meansfor pivotally relating one end of said control link and one of saidsupports, a second main supporting link substantially longer than saidcontrol link, means pivotally relating one end of said main supportinglink to said one of said supports at a point spaced both vertically andhorizontally from the pivot point of said control link, a movable memberhaving a plurality of pivot points thereon, means pivotally relating oneof said pivot points and the other end of said control link, meanspivotally relating another of said pivot points and the other end ofsaid main supporting link, a switch blade rigidly fastened andelectrically connected to said member and arranged to move toward andaway from said stationary contact during closing and opening of saidswitch in response to movement of said member, a rotatable insulatorsupported for rotation by said one of said supports, a crank armrotatable with said rotatable insulator, and means comprising auniversal link interconnecting said crank arm and said member fortransmitting an operating force causing rotation of said insulator tosaid member, said links and member being so related that operation ofsaid last mentioned means causes swinging movement of said switch bladefor the major portion of its movement together with an endwise movementof said switch blade along its longitudinal axis when said switch bladeis near its closed circuit position, said operating force being appliedto said mechanism in all positions of said switch blade through a leverarm at least as long as the longest of said links.

6. In an electric switch, a pair of spaced insulators, a pair ofsupports one mounted on each of otally relating one end of said firstlink and one of said supports, a second link of different length thansaid first link, means pivotally relating one end of said second link tosaid one of said supports at a point spaced from the pivot point of saidfirst link, a movable member having a plurality of pivot points thereon,means pivotally relating one of said pivot points and the other end ofsaid first link, means pivotally relating another of said pivot pointsand the other end of said second link, a switch blade rigidly fastenedand electrically connected to said member andarranged to move toward andaway from said stationary contact during closing and opening of saidswitch in response to movement of said member, rotatable means includinga crank arm disposed between said spaced insulators and at leastpartially supported for rotation by said one of said supports, and meanscomprising a universal link, interconnecting said crank arm and saidmember for transmitting an operating force causing rotation of saidinsulator to said member, said links and member being so related thatoperation of said last mentioned means causes swinging movement of saidswitch blade for the major portion of its movement together with anendwise movement of said switch blade along its longitudinal axis whensaid switch blade is near its closed circuit position, a line throughthe pivot points of said control link closely approaching the rightangle with the longitudinal axis of said blade throughout the swingingmovement of said blade.

HAROLD E. SEAMAN. LESTER C. HART.

REFERENCES CITED The following references are of record in the file ofthis patent:

UNITED STATES PATENTS Fjellstedt et al Nov. 27, 1934

